1. Field of the Invention
The present invention relates to a dental adhesive (or cement), composition usable for adhering and firmly fixing dental restorative materials comprising ceramics such as calcium metaphosphate crystallized glass, and further, for example, alloys, porcelain materials, and/or composite resins, to the teeth.
2. Description of the Related Art
Various dental adhesives have been utilized for the therapy of teeth suffering from caries, such as zinc phosphate cement, carboxylate cement, glass ionomer cement, etc. Further, in recent years, as a newer type of dental adhesive, composite resin cements containing a vinyl monomer having phosphoric acid group or carboxylic acid anhydride group in the molecule, such as 4-methacryloxyethyltrimellitic acid anhydride and methacryloxyethlyphenyl hydrogen phosphate, are now commercially available. This composite resin cement can be used for the adhesion of a crown, or inlay to the teeth, and further, can be itself utilized as a dental restoring material by reinforcing the adhesion to the teeth by using another dental adhesive composition in combination therewith.
On the other hand, aesthetic considerations in dentistry have become important recently, and various new material ceramics have been developed in response to this need. Particularly, because castable ceramics such as calcium metaphosphate crystallized glass have characteristics similar to natural teeth in mechanical strength and the aesthetic sense, they are suitable for use as a dental restorative material. However, when utilizing such a material, a dental adhesive composition must be used for adhering and firmly fixing the dental restorative material comprising castable ceramics.
However, the dental adhesive composition of the prior art, although having a good adhesive force between teeth and a dental restorative material comprising, for example, an alloy, a porcelain material, or a composite resin, is not able to firmly adhere the dental restoring material comprising castable ceramics to the teeth, and a dental adhesive composition for such castable ceramics has not been proposed in the prior art.
Accordingly, a dental adhesive composition effective for adhering and fixing a dental restorative material comprising castable ceramics such as calcium metaphosphate crystallized glass to the teeth is desired.